The present application for a Patent of Invention relates, as indicated in its title, to a xe2x80x9cLONGITUDINAL GUIDANCE CONTROL SYSTEM FOR TELESCOPIC SHAFTS AND/OR ASSEMBLIES WITH COLLAPSING MECHANISMS IN MOTOR VEHICLE STEERING COLUMNSxe2x80x9d whose new characteristics of construction, form and design fulfil with maximum reliability and efficacy the purpose for which it has specifically been designed.
More specifically, the invention relates to a purely mechanical arrangement applicable to steering column mechanisms and which allows a range of functions, such as guidance of the column, both in the veritable and longitudinal directions, adjustment thereof so that the same type of column may be adapted to various types of vehicle by reducing or increasing the working length thereof, as well as the collapsing system provided in the majority of steering columns installed in vehicles in which, in the event of an accident and after travelling along a safety length, the steering shaft or male member collapses on another shaft, also known as a female member, which, in combination with said steering shaft, comprises the means necessary for absorbing the impact energy resulting from the pressure applied by the user, who transmits to the steering wheel with his/her hands the force generated by the impact, the steering wheel then transmitting it to said steering column or male member.
A plurality of steering systems exist on the market, and may therefore be regarded as prior art, which are basically arranged between the steering box and the steering wheel situated at the opposite end.
Between the two, steering wheel and box, there is located the steering mechanism proper formed of a male member or steering column which extends into a female member.
The lateral surface of the male member comprises the means necessary for fitting together with other means arranged on the internal lateral surface of the female member, in such a way that, in a first instance, they may be coupled together in a fixed manner, so that the surface or turning force exerted on the steering wheel may be transmitted from the male member to the female member without any type of displacement between them.
Likewise, said lateral surfaces of the male member and female member comprise other means which allow longitudinal guidance of the male member with respect to the female member, for the purpose of relating the length of the steering system to the dimensional characteristics of the vehicle, in such a way that said system may be shortened or lengthened without the need for providing different types of steering mechanism.
Likewise, said steering mechanisms incorporate collapsing systems which allow absorption of the energy applied to the steering wheel in the event of impact, in such a way that the male member may enter the female member, absorbing the impact energy, without the steering column shaft being driven into the front of the user.
All of the above should be combined with other means which simultaneously allow longitudinal displacement of the steering, in the event of the vehicle being equipped with this type of means or indeed, as stated above, with other means which permit adjustment of the length of the steering system to the greater or lesser size of the user, irrespective of the means, already mentioned, for customised positioning of the steering system in accordance not with the characteristics of the user but with those of the vehicle itself.
The object of the present invention is to provide a guidance system which is not only perfectly compatible with the relative displacement between the components of the steering column (male and female members), but also permits optimum control of the movement between the two by means of the connection together of all the mobile components with respect to those which remain stationary, resulting in a proposed mechanical arrangement which is effective at the same time as being of great structural simplicity and very simple to assemble and at the same time as being very cheap to manufacture.
In those telescopic mechanisms which constitute part of the prior art and also in those collapsible installations in which two assemblies have to move relative to one another at a defined instant and under a certain load, it is indispensable for a system to be provided which allows guidance of the mobile assembly in relation to the stationary assembly in a continuous and controlled manner.
The system proposed in the present invention ensures the above mentioned guidance, specifically for steering columns present in motor vehicles, but this does not exclude the possibility of its being used for other applications, owing to its simplicity and ease of functioning.
The present invention relates to a guidance system which permits precise directional control during the relative displacement of two units which, although it may optionally admit of other applications, has been specifically designed for incorporation into for motor vehicle steering columns, that is to say in mechanisms used for transmitting rotation from the steering wheel to the steering box of the vehicle.
More specifically, the present invention relates to telescopic systems and/or systems with integral collapsing mechanisms which experience longitudinal displacement of some components relative to others, which remain stationary, under certain load conditions liable to actuate the telescopic adjusting mechanism, when it is wished to vary the height of the steering wheel relative to the driver or when it is sought to ease mounting of the assembly in the vehicle or when, in the face of an impact, the steering system performs its role as a vehicle safety system.
The proposed system comprises a column support which is secured in the strong structure of the motor vehicle bodywork and which has a lug at one of its ends, i.e. the opposite one from the steering wheel, in which there is articulated a pivoting bearing of the steering column proper, said support being held by an intermediate component sliding under certain conditions with respect to said column support and a lower mobile component which is displaceable longitudinally and veritally, actuated directly by an adjusting mechanism, which, via this component, permits the adjustment in height and depth of the steering column.
As is well known, the telescopic and collapsing functions are usually effected by the assembly formed by at least two members tubular in form or having a suitable profile to allow telescoping of one into the other and which remain suitably fixed in a predetermined relative position until such time as said position changes in conjunction with the length of the assembly, when the latter is subject to a predetermined axial force.
Nevertheless, the steering column of the vehicle consists not only of the above-mentioned sliding elements but also of other components, the purpose of which is to effect various other functions with which this important system is entrusted.
In any event, it is essential that all those members of the column, accessories and auxiliary components and those which are to effect displacement relative to the remainder of the components which attach the column to the vehicle and which remain stationary during said movement, do not exhibit any friction of any kind nor present any hindrance to the movement thereof.
Other details and characteristics of the current application for a Patent of Invention will become clear from a reading of the description given below, which refers to the drawings accompanying this specification and in which the details referred to are shown schematically. These details are given by way of example, referring to one possible practical embodiment which is not limited to those details described here; therefore, this description should be regarded as an illustration, not limiting in any way.